Indeed an excellent episode. I'd forgotten all about Kakuzu's beat down of poor Izumo and Kotetsu but the anime made the fight look pretty cool IMO. Kakuzu is one of my favorite characters in the series. He acts te most like what I'd want a badass evil ninja to act like. He does bad things, but he does them like a Ninja would, coldly calculating and assessing the cost and benefit of actions and then taking the one that seems most prudent.

Oro behaves like a psycho, Itachi like an emo, Sasori was just creepy and basically a bratty little kid with butt loads of power (much like Hidan and Diedara seem to be) but Kakuzu seems like an uber ninja who knows what he wants and goes out and gets it and doesn't waste time or effort on unnecessary or unimportant things.